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new here..have question..pleeease help :(

  • Thread starter Thread starter t_stang00
  • Start date Start date Sep 4, 2009

t_stang00

New Member
Sep 4, 2009
53
0
0
Sep 4, 2009
#1
  • Sep 4, 2009
  • #1
OK, so, my 00 gt. hmm..wer to start..
the symptoms:
Very light knocking
overheats
and white smoke exhaust


wat u guys think?
im being told most likely head gasket..but i wanna know wat i COULD face..so im not overly shocked..if that dont fix it..
i also would like to know..
If you were to spend 1000.00 upgrading the performance on a stock gt 5spd..wat would u buy?
thats about all i wanna spend right now on upgrades..and i want the most power for the money
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Sep 4, 2009
#2
  • Sep 4, 2009
  • #2
1) these cars do not blow head gaskets

2) before you worry about "performance" get your car running properly!
 

t_stang00

New Member
Sep 4, 2009
53
0
0
Sep 4, 2009
#3
  • Sep 4, 2009
  • #3
could

could it be cracked head gasket?
and i keep hearing..these cars dont blow head gaskets..and i did a searh on the forum for head gasket..and many people have blown theres..or had them go bad..with everyone still saying that it wasnt tht..so i do believe it could be this..because it CAN happen..and HAS happend..
but i also would like to know other options..so if its not head gasket..ik wer to look..thx for all help i get
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Sep 4, 2009
#4
  • Sep 4, 2009
  • #4
t_stang00 said:
could it be cracked head gasket?
and i keep hearing..these cars dont blow head gaskets..and i did a searh on the forum for head gasket..and many people have blown theres..or had them go bad..with everyone still saying that it wasnt tht..so i do believe it could be this..because it CAN happen..and HAS happend..
but i also would like to know other options..so if its not head gasket..ik wer to look..thx for all help i get
Click to expand...

Any car, especially one with aluminum heads, can blow a headgasket. AFAIK, the 4.6L mod motor is not known to be a habitual gasket-blower. That is, it's not "prone" to this. With millions in service in taxi and police fleets, we'd know by now if this was the case.

But if the car is overheated severely, the head casting can warp resulting a head gasket leak. If it's run for an extended period without an accessory belt (i.e. the waterpump doesn't turn) or with with low coolant, it can and likely will have issues. Severe detonation can also damage gaskets.

The problems you're experiencing certainly have the hallmarks of a head gasket issue.

What's the full story? How'd this come about? Your sig says the car is bone stock: Have you had it since new? Has it always been stock?
 
T

tragikk

New Member
Aug 29, 2009
15
0
0
Pennsylvania
Sep 4, 2009
#5
  • Sep 4, 2009
  • #5
does the oil on your dipstick look like chocolate milk? not trying to be funny either.. like others have said it could be a head gasket or it could be the head. have the cooling system pressure tested.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Sep 4, 2009
#6
  • Sep 4, 2009
  • #6
tragikk said:
does the oil on your dipstick look like chocolate milk? not trying to be funny either.. like others have said it could be a head gasket or it could be the head. have the cooling system pressure tested.
Click to expand...

Good point. When coolant mixes with oil, you often get a light-brown milkshake-like colour. Since pressurized oil travels up to the head and unpressurized oil drains back to the sump from the heads across the headgasket interface, oil and water mixing could easily happen if the gasket is bad.

The overheating and steaming exhaust are pretty bad signs. I have to wonder if the overheating appeared first -- perhaps caused by a bad thermostat or something -- then caused a head to warp and now it's still overheating and burning water etc...
 
C

camon

New Member
Sep 19, 2005
29
0
0
Sep 5, 2009
#7
  • Sep 5, 2009
  • #7
Sounds like Head gasket to me!

Get a compression gauge on those cylinders and check compression!

Overview of procedure:
1. Take all spark plugs out on the engine (all plugs must be removed)!
2. Screw compression gauge into a spark plug hole.
3. Hold throttle wide open and crank the engine 4 revolutions.

Repeat this for every cylinder (having a 2nd person helps in determining engine revolutions). You can count engine revolutions by watching the compression gauge needle jump (it will jump 4 times, once for every revolution). Record reading and move onto the next cylinder!

You want every cylinder within 8-10 psi of each other! Lower compression
on 1 or 2 holes (next to each other) is a sign of a leaking head gasket between them holes.

You aren't concerned so much about the high readings (although it is important), for a leaking head gasket you are worried about the difference between cylinders!

Example: #1=160, #2=160, #3=155, #4=160, #5=130, #6=135, #7=160, #8=160 (This example shows a leakage problem with #5 and #6, Gasket blown between the 5 and 6 cylinder)!

Hope this helps!
 

t_stang00

New Member
Sep 4, 2009
53
0
0
Sep 5, 2009
#8
  • Sep 5, 2009
  • #8
Thanks Coman! thats what i think ill try first!...im having him check the oil for the color this weekend.
If thats not the problem, ima take the heads to a machine shop and see it theres any cracks that i wouldnt be able to see..and have valves checked....anyone have any other input?
 

bhuff30

Founding Member
Dec 11, 2001
6,037
35
129
Olathe KS
Sep 5, 2009
#9
  • Sep 5, 2009
  • #9
There are a lot of possible causes for white smoke. I've heard of cracked plastic intake manifolds causing white smoke as well, and that is a very simple fix (especially compared to a headgasket). On the other hand, my 88 was acting like it had a blown head gasket... mixed fluids, white smoke, missing on one cylinder, and I discovered a 6" crack in the cylinder wall. So you never know. Do a compression check, check the intake manifold, and take things apart to find the real cause. Again, head gasket issues on the 4.6 are very uncommon, but anything is possible. No matter what, it is impossible for us to diagnosis it by the internet. You'll have to do the test and just start taking stuff apart.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Sep 5, 2009
#10
  • Sep 5, 2009
  • #10
camon said:
You can count engine revolutions by watching the compression gauge needle jump (it will jump 4 times, once for every revolution).
Click to expand...

Actually, it'd jump once every two revolutions.
 

t_stang00

New Member
Sep 4, 2009
53
0
0
Sep 6, 2009
#11
  • Sep 6, 2009
  • #11
ssooo

before i do anything..
is 1 jump per revolution...or is it 2 jumps???

where can i buy a compression guage?
 
T

tonytaylor85

Member
Sep 3, 2009
126
0
17
Augusta GA
Sep 6, 2009
#12
  • Sep 6, 2009
  • #12
Any self respecting auto parts store will have one. You will see it jump every other revolution. Most have a check valve and it will not drop the needle until you release the pressure. The first cycles will be low. You should see max readings by the third compression stroke.
Many of those kits come with leakdown test fittings where you can put compressed air into the cylinder and listen for the leak. intake or exhaust means a leaky valve, bubbles in the coolant tank mean head gasket or crack. Thru the valve cover is a damaged piston or ring.
 
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